British Rail Class 168
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The Class 168 Clubman is a diesel multiple-unit train used by Chiltern Railways between London and the Midlands. They were built in several batches from 1998 onwards. The first batch of units was classified 168/0 under TOPS and bore a large resemblance, both visually and in terms of electrical design, to the Class 165 units previously built by BREL at York. Subsequent builds, classified 168/1 and 168/2, were given the newer Turbostar-style cab and a new design of wiring.
In fact, the 168 is, in terms of engineering, a Turbostar in all but name.[citation needed]
The Turbostar platform is a modular design, optimised for speedy manufacture and easy maintenance. It consists of an underframe, which is created by seam-welding a number of extrusions, upon which bodyside panels are mounted. A single piece roof, again made from extruded sections, is then bolted on. The car ends are made from GRP and steel, and are bolted on. Underframe components are collected in ‘rafts’, which are bolted into slots on the underframe extrusion.
The drive system consists of a MTU diesel railcar engine, close-coupled to a Voith T211r hydrodynamic transmission. This is the same gearbox as previously used on all Sprinter variations. It has two speeds, the first one being a torque converter drive and the second a fluid coupling. A cardan shaft links the output of the gearbox to ZF final drives on the inner bogie of each vehicle.
The most important differences between the 168 fleet and Turbostars, as far as drivers are concerned, is the provision of Automatic Train Protection (ATP) equipment, manufactured by Alcatel, and the tripcock system for operation on tracks shared with London Underground. Additionally, the Class 168 can only be coupled to Class 165 and Class 166 DMUs, as these three DMU classes have a different pattern of electrical studs on their coupler faces, a result of British Rail’s desire to prevent the latter two DMU classes from being reused by the Regional Railways sector.[citation needed]
As with the Turbostars, reliability problems were rife at the outset, but considerable effort was made by the manufacturer ADTranz (now Bombardier Transportation) to improve their record. The Turbostars are now widely considered the most reliable of the third-generation short-haul DMU fleet in Britain. However, some subsystems on board continue to suffer from reliability problems due to the poor quality of the components. The most obvious example is the passenger information system, which is based on GPRS and GSM technology, but frequently fails to accurately find its position, resulting in misleading information being displayed to passengers. This problem is prevalent throughout the Turbostar fleet.
